Free Tool

French Drain Calculator

Estimate pipe, gravel, fabric, and total cost for a French drain installation. Compare DIY and professional pricing.

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$199
DIY materials cost
$1,100
est. professional
Pipe: 50 ft
Gravel: 1.4 cu yd
Fabric: 50 ft
Slope: 6.3" min drop

Need to plan your drain path? View your yard on satellite imagery with LotSite →

Cost Comparison

French Drain Cost by Length

DIY vs professional installation costs for standard 4-inch drains.

25 ft drain
Gravel
0.7 cu yd
DIY
$100
Pro
$550
50 ft drain
Gravel
1.4 cu yd
DIY
$199
Pro
$1100
75 ft drain
Gravel
2.1 cu yd
DIY
$299
Pro
$1650
100 ft drain
Gravel
2.8 cu yd
DIY
$399
Pro
$2200
150 ft drain
Gravel
4.2 cu yd
DIY
$598
Pro
$3300
200 ft drain
Gravel
5.6 cu yd
DIY
$798
Pro
$4400
Drainage Guide

French Drain Installation Guide

A French drain is a gravel-filled trench with a perforated pipe that collects and redirects water away from problem areas. It is one of the most effective solutions for wet yards, soggy spots, and foundation drainage issues.

The key to a successful French drain is proper slope. The trench must slope at least 1 inch per 8 feet (1 percent grade) toward the outlet point. Use a laser level or string level to verify consistent slope before laying pipe. The outlet can be a dry well, a storm drain, or a lower area of your property.

Use LotSite to plan your drain path on satellite imagery. Viewing your property from above helps you identify the best route from the problem area to the outlet point, and estimate the total length needed.

FAQ

Frequently Asked Questions

Plan your drainage on satellite imagery

Enter your address to view your yard and plan the best drain route.

Also check out our gravel calculator and retaining wall calculator